Citation and License

Nutrition Journal 2011, 10:92
doi:10.1186/1475-2891-10-92

Published: 13 September 2011

Abstract

Introduction

Dehydration and malnutrition commonly occur together among ill children in developing
countries. Dehydration (change in total body water) is known to alter weight. Although
muscle tissue has high water content, it is not known whether mid-upper arm circumference
(MUAC) may be altered by changes in tissue hydration. We aimed to determine whether
rehydration alters MUAC, MUAC Z score (MUACz), weight-for-length Z-score (WFLz) and
classification of nutritional status among hospitalised Kenyan children admitted with
signs of dehydration.

Study procedure

We enrolled children aged from 3 months to 5 years admitted to a rural Kenyan district
hospital with clinical signs compatible with dehydration, and without kwashiorkor.
Anthropometric measurements were taken at admission and repeated after 48 hours of
treatment, which included rehydration by WHO protocols. Changes in weight observed
during this period were considered to be due to changes in hydration status.

Results

Among 325 children (median age 11 months) the median weight gain (rehydration) after
48 hours was 0.21 kg, (an increase of 2.9% of admission body weight). Each 1% change
in weight was associated with a 0.40 mm (95% CI: 0.30 to 0.44 mm, p < 0.001) change
in MUAC, 0.035z (95% CI: 0.027 to 0.043z, P < 0.001) change in MUACz score and 0.115z
(95% CI: 0.114 to 0.116 z, p < 0.001) change in WFLz. Among children aged 6 months
or more with signs of dehydration at admission who were classified as having severe
acute malnutrition (SAM) at admission by WFLz <-3 or MUAC <115 mm, 21% and 19% of
children respectively were above these cut offs after 48 hours.

Conclusion

MUAC is less affected by dehydration than WFLz and is therefore more suitable for
nutritional assessment of ill children. However, both WFLz and MUAC misclassify SAM
among dehydrated children. Nutritional status should be re-evaluated following rehydration,
and management adjusted accordingly.